EQUALLY EQUIPPED (In my case, with an 18 inch rail and equivalently long bellows), I find the Norma only about a pound heavier than the F2. It is a little bulkier, but more rigid too. They do need to be tuned up from time to time, which is fairly straightforward once you've learned how. I'd avoid an F+ or F1 unless you find a bargain one for sake of spare components; the front standard is less durable, and really just the same thing as an "intermediate bellows standard". Any of them are quite usable in the field. But no matter which specific model, with a Sinar you're buying into a very large system of options. Nearly everything is interchangeable. The only exception would be the oddball ultralight A1 Alpina, which has a completely different rail profile.